Hands On With Delta P’s BREVIS II, 3D Printed Suppressors

While visiting friends in Portland, Oregon, I realized that Portlandia isn’t a very creative show. It’s actually more observational; practically a documentary. Seriously, how does a button store or a terrarium store or three piano stores within a half mile of my friend’s place survive? Maybe they’re just trustafarians selling pianos ironically? Anyway…silencers. Delta P Design makes the BREVIS II family of compact rifle suppressors, which piqued my interest at SHOT Show 2015. Not only are they really freaking compact and mind-bogglingly lightweight, but they’re the first 3D printed suppressors on the market. That makes them cool. But to find out if they actually work, I escaped Portland, drove a half hour south, and met up with the guys from Delta P for a range day. . .

“3D Printed” can refer to a handful of types of additive manufacturing processes, and Delta P isn’t using the MakerBot-squirting-melted-polymer method we typically think of. These suppressors are manufactured via a DMLS — direct metal laser sintering — process. In general, this means a very thin layer of very fine metal powder is deposited onto the work surface, and then a high-powered laser fully fuses — sinters — only specific areas of that layer to the previous layer. One super thin slice at a time, your object coalesces in the full meaning of the word, as the final product is not separate layers “glued” together but, truly, one homogeneous, monolithic unit.

All sorts of advantages can be had through DMLS as compared to machining, casting, and other manufacturing methods, and Delta P is putting many of these to good use. In fact, they made it quite clear to me that they came to DMLS as the only means of turning their unadulterated silencer designs into reality. Creating a 3D Printed silencer was not their intention, and the engineers who own and run the company actually kept the manufacturing method entirely under wraps until now in the fear that it might be perceived as a sales gimmick. So, again, they stressed that Delta P wasn’t started to see if 3D Printed silencers would work. Rather, they engineered what they thought would be the best silencer design possible and then realized DMLS was the only real way to actually manufacture it.

“Compact” doesn’t adequately describe just how small these things are. In the photo above, that’s a raw finish .223/5.56 BREVIS II sitting next to a SureFire X300. The can is like an 1/8th of an inch longer. On paper, the BREVIS II clocks in at a stubby 3.7″ long in 5.56 flavor and 5.5″ long in the larger caliber variants.

Oh, and the 5.56 Ultra only weighs 6.6 oz. That’s insane! But more on this later, as I have to geek out on the size and design for a while first…

When I saw them at SHOT Show I thought the size was obviously super cool — adding only ~twice the length of an A2 Birdcage, a BREVIS II-equipped patrol rifle will still fit in standard cruiser mounts and is sure handy for vehicular ingress/egress and working in small, interior spaces — but figured there’s no way they’re anywhere near hearing safe! Of course, I managed to forget that the radius is squared when calculating the volume of a cylinder. Thanks to the BREVIS’ larger diameter, the 5.56 model has the same interior volume as if it were a 6.5″-long, standard-diameter silencer.

BREVIS II 5.56, PMAG, BREVIS II 7.62

Internal volume, really, is the name of the game when it comes to silencer efficacy, but obviously as size goes up so does weight. As a tube’s pressure-holding strength decreases as diameter increases — given the same tube wall thickness — we find most rifle silencers stick to a fairly standard diameter. To increase interior volume they get longer, not wider, mostly for this reason. Additionally, with standard manufacturing processes, a longer can means more baffles.

DMLS offered the ability to create interior features that would be impossible through traditional means or, at least, effectively impossible due to the complication and outrageous costs required. It also wouldn’t be anywhere near as strong as Delta P’s DMLS design, which results in a one-piece product. No welds, no threaded-in parts, etc. As an example, not only is the mount completely integral rather than a welded-on or screwed-in piece like with every other can, but it’s the very same piece of metal as both the body and the internals and flows directly into some of the internal support structures. Forces on every part of the silencer can be distributed and shared in ways that are impossible otherwise.

This is one of the reasons the BREVIS line can employ a wide diameter while, in 5.56, still being rated for use on barrel lengths as short as 7″. I don’t recall if there are restrictions on the .30 cal can, other than it’s officially rated for at least .300 RUM and is a-okay for full-auto .308 on a 16″ barrel.

The one unique internal feature that I can share — the one I know of and one of the ways they’re taking advantage of 3D printing — is that the blast/expansion chamber is significantly larger than you’d expect. Larger than the norm, in fact, which means a faster pressure drop as gasses exit the muzzle, which means a bit less blowback through the firearm’s action than the norm. Basically, imagine a normal-diameter baffle stack tube inside of the larger-diameter BREVIS body, and “float” the nicely-sculpted blast baffle in space except for some supports that connect it to the body. Now your blast chamber extends the entire length of the suppressor. Then the inner core is basically normal in diameter. Putting my imagination and MS Paint skills to work (and leaving out support structures since they would look like gas-stopping walls), in cross section it’s something vaguely like this:

To be clear, I created the amazing drawing above based on my own assumptions. It’s certainly incorrect, as I don’t know what’s actually inside of the core part, what’s inside of the blast chamber part, or whether gas can exchange between the two anywhere other than via the bore. It also grossly simplifies the complex, sculpted, interconnected internals that only 3D printing could accomplish. But, looking down into the can through the mount, it’s apparent how the blast baffle allows gas to go around it and down along the silencer’s walls to create a huge blast chamber volume.

So the small size is awesome, of course, and the information gleaned above was meant to convince me that a 5.56 BREVIS II is physically capable of being just as quiet as a longer-but-skinnier market standard like the AAC M4-2000. But one of the other advantages of DMLS manufacture is the unencumbered ability to put material where it’s needed and only where it’s needed.

This, combined with the monolithic nature of the BREVIS II, is why it can be so incredibly lightweight yet even stronger than the norm. Whether it’s the standard model, which is 100% Inconel, or the Ultra model, in which key parts like the blast baffle are Inconel but most of it is titanium (but it’s all one, solid piece of metal regardless), these silencers are way lighter than their competition. The numbers break down like this:

BREVIS II 5.56: 11.5 oz

BREVIS II ULTRA 5.56: 6.6 oz

BREVIS II 7.62: 16 oz

BREVIS II ULTRA 7.62: under 10 oz

There are also cans for 6.5mm and 8.6mm (think .338 Lapua Mag) calibers, and, like the 5.56 and 7.62 flavors, they weigh from as little as 1/4 up to about 1/2 of what their competition weighs. As an amusing exercise, Delta P’s .338 Lapua can weighs 10 ounces. Go forth and Google, and compare that to its peers.

On The Range

Small, light, and unique. Check. But they ain’t cheap. You may go down by [at least] half on the weight but you’re likely to go up by half on the price. So they have to perform, and perform well.

They definitely do that on strength. The 5.56 and 7.62 silencers are full-auto rated to shorter barrel lengths than the competition. During our time on the range, we shot the BREVIS II 5.56 on a 6″ barrel (officially, it’s rated for 7″+) and it shrugged that right off, of course.

While it can’t quite quiet things down to under the OSHA-suggested 140 dB max level on that short of a barrel, it does get rid of all of the brain-rattling concussion and turns the beach ball-sized fireball into a bad memory. I’ll actually be borrowing one for the next 5.56 flash hiding test because of how extremely impressive it is in this role. In the meantime, here’s a quick video that shows 5.56 through a 6″ barrel with and without the BREVIS II attached, and shows both a well-known competitor’s .30 cal can and the BREVIS II 7.62 on either a 16″ or 18″ (I don’t recall which) barrel shooting .308 Win.

As for the BREVIS II’s volume levels on various barrel lengths for both 5.56 and 7.62:

5.56 (Federal M855) on 16″ bbl: 134-135 dB

5.56 (Federal M855) on 10.3″ bbl: 138-139 dB

7.62×51 (M80 ball) on a 24″ bbl: 135-136 dB

7.62×51 (M80 ball) on a 20″ bbl: 138 dB

Compared to their peers they’re solid performers but they aren’t breaking records. Well, other than what I think are length, weight, and sound suppression per inch/ounce records. Of course, dB meter readings don’t correlate exactly with the human ear’s perception of loudness. Two suppressors metering at the exact same sound pressure level can actually sound quite different in person — one noticeably “louder” than the other — due to tone, peak duration, and other factors.

From what I’ve experienced personally as well as heard from others, in general a deeper tone will seem quieter. For example, 135 dB at a higher frequency is more likely to cause discomfort than 135 dB at a lower frequency, and will generally be perceived as being louder. Some suppressors have positive reputations for producing a “low tone.” When there are enough of Delta P’s BREVIS IIs out there to build up a reputation (note that they are a generational improvement over the original BREVIS models), they’ll be known for this sort of complimentary tone. The interior volume, design of the large blast chamber, and solidity of the monolithic structure combine to product a solid, lower-pitched tone.

Ownership

These are supposed to be lifetime suppressors. They can be pinned and welded onto a barrel to bring it up to a certain length (I’d like to use the 7.62 Ultra on a .300 BLK upper, permanently attaching it to bring the effective barrel length just to 16″), and barrels can be cleaned in the normal fashion with the can on the end. In fact, the whole idea is to basically treat a BREVIS II like any other muzzle device — flash hider, muzzle brake, etc — and consider it a more or less permanent part of the barrel, simply leaving it in place.

Leading and carbon buildup is not much of a problem with centerfire rifle rounds, but if desired these suppressors can be cleaned in an ultrasonic tank, with brake/carb cleaner, via “the dip” (soaking in a 50/50 white vinegar and hydrogen peroxide solution to dissolve leading — just note lead acetate safety precautions), etc. Basically, don’t get hung up on the “3D printed” thing, because there are no limitations on these cans that wouldn’t also apply to one made from a solid billet of Inconel or titanium.

I was able to inspect a BREVIS II 5.56 with, according to Delta P, coming up on 10,000 rounds through it — much of that on a stubby barrel, including under full-auto fire — and the only sign of wear or degradation was minor pitting around the bore hole of the blast baffle. I don’t think it was enough to change the effective hole diameter, but the once-crisp, clean edge was now a bit fuzzy. Use was evident from heat-induced coloration on the exterior, burned on carbon staining on the interior, etc, so the thing was clearly run hard.

The Ultra (Ti) versions are just as tough as the 100% Inconel standard versions outside of sustained, full-auto use. They have the advantage of being lighter, but the disadvantage of being more expensive.

Conclusions

Unfortunately, due to the nature of NFA items I can’t do a full review on a BREVIS II without buying one, paying the $200 transfer, waiting the ~6-9 months, etc. If I decide to buy a dedicated 5.56 can at some point I probably will be calling up Detla P. For now, though, this is just an “initial impressions,” range review sort of a post and it’s a bit limited in that as well, since shooting at a public range mandated wearing ear pro the entire time and meant shooting under a tin roof and near a concrete wall as seen in the video.

What I can say for sure is that the BREVIS II 7.62 on an AR-10 sounded just as quiet as a significantly larger, heavier can from a well-known manufacturer (if it were an actor, it would be an A-list celeb), that all of the BREVIS II line produces a nice, low tone, and that they appear to be rock solid.

Oh, and when you pick up the 6.6 oz 5.56 Ultra you giggle and think it’s some sort of joke. Cover the hole on either end and the darn thing will float. It’s basically impossible to feel a difference in rifle balance or handling between a bare muzzle and an Ultra-equipped muzzle. That’s sort of awesome.

comments

If there was enough interest I’d be wiling to start a Kickstarter (or whatever) campaign to raise the funds for those sort of shenanigans…specific “tests” as they arise but are out of the budget. Or I’ll keep trying to win the lottery haha

Of course, if Delta P wanted to share I suspect they could pretty simply “print out” half a suppressor. No need to manufacture an actual, serialized silencer and then cut it in half when I bet whatever CAD program they use could do the dirty work in like 30 seconds and then they could DMLS the half-can from it.

LOL true. While on the range I actually asked them if they thought of doing a “cutaway” model for trade shows and such, and it sounds like they’re a bit conflicted with that. On the one hand they do want to show off what’s going on inside there (to “wow” prospective buyers), and on the other hand they want to keep it secret (for competitive purposes).

…on a related note, I used to work for a car manufacturer and they purchased cars from competitors to tear them apart and check them out, and competitors purchased their cars to do the same. No secret that it goes on. All of the manufacturers do that to understand their competition. And you can’t prevent it, as manufacturers would just buy them at retail through a proxy. So if any of the silencer manufacturers really want to know what’s going on inside of a BREVIS II, they could do the same. But no reason for Delta P to make it easy and free for them by putting a cutaway on display, either haha

Jeremy S suggests that competing manufacturers could buy each other’s products and saw them in half to see how the work. I recall a Leghorn article about hanging out with the guy originally from AAC (now with Sig I believe) who had a table of competitors’ sawed-in-half products like he suggested. So yeah, they do exactly that.

That being said, these are a great idea. I’m having a hard idea coming up with a scenario where that wide of a can would fit under a handguard for permanent attachment to a sub-16″ barrel, but I love the fact that I can. In theory.

Why does it need to fit under handguards? My can sits in front of my handguards, which stop at the end of my 9″ barrel, and it works fine. Or at least it did, before I saw it could be a pound lighter! Surrounding the can with handguards make it all heavier still, I want it LIGHTER!!

The article suggested pinning & welding it onto a .300BLK barrel. What I think WedelJ means is that if it was pinned&welded to a barrel, you would never be able to disassemble the upper – because the handguard would not be able to slide over a fat can like this. If you can’t remove the handguard, then you can’t remove the barrel from the upper etc. You end up with everything being permanently affixed … just at the first point of takedown.

I think the whole tax stamp thing makes it even more likely that I would personally buy a high-end suppressor instead of a less expensive one. If I’m going to shell out $200 in tax no matter what suppressor I get and wait 4 to 6 months before I can even pick it up, I’m going to want to get something that lasts a long time and works well. When I bought my .22 can I was originally looking at one that sells for like $199. But a $200 tax on a $199 can was kind of painful and I went with a $450 can instead. It’s tougher and should last a lifetime. It just wasn’t worth saving that cost difference to me considering the hassle and the tax, etc…

Me, too, absolutely. I can afford it, why settle for less? SigSauer’s handout on silencers describes Hiram Maxim’s invention of silencers in 1909, and sale of same through hardware stores and mail order, for $3.25 each until leaving the market (guess when) in 1934 in response to NFA. I would prefer cheap and easily replaceable cans, but with current law I want my purchase to be the best performance and last forever, damn the cost.

Sorry, Tom! I actually don’t know where abouts in Oregon you are, but should have hit you up to find out. I also didn’t call Joe Grine, though, even though I know he’s in the Portland area. This range trip was last minute and at like 6:30 AM so you’re probably lucky I didn’t ring you up haha

Very cool. I’ve been thinking about dedicated 556 silencer as part of an SBR build. Hmmm.

What does one of the DMLS rapid prototyping machines cost today? $50K? $100K? The nature of this technology is that it is likely in a 10 years for a normal guy to have a machine that can make small parts like this in his basement. I can’t wait.

The Delta P is an amazing piece of engineering, adding a very neat twist to the traditional baffle stack design by adding a massive expansion chamber with the baffle stack precisely centered in a manner that would be impossible, or at least prohibitively expensive to do with traditional reductive machining technologies

Given that, I’d like to see someone make a design like the OSS systems that redirects the gasses through a series of turbine fan-like stationary blades, and utilize the advantages of DLMS to make a non-traditional can that can fit a large portion of the can around the barrel and inside the handguard. DLMS would allow for very odd and irregular shapes other than the traditional round or rectangular metal tube that most silencers are today.

Unlike the baffle stack design, which reduces noise signature by trapping the gasses and allowing them to gradually exit, which is effective, but also has negative side effects in the form of over pressuring the gas system due to the backpressure induced by stopping the gasses, the OSS design redirects the gasses through a series of jet turbine like stationary blades, allowing the gasses to dissipate their energy gradually, while reducing backpressure significantly.

Also, if the proposed legislation to deregulate suppressors goes through, I’d expect to see some movement on mass produced sintered products from Ruger. They’ve been doing MIM and investment casting in aluminum, steel and titanium for a long time, and are really, really good at it. Since Bill Sr passed away, Ruger has been bringing some very cool products to market, and I think they’d be ecstatic to start selling affordable monolithic suppressors to the masses.

One downside to the OSS concept is size and weight. Since it’s small channels directing gas back and forth through the system instead of baffles between open air spaces, there isn’t as much empty space per inch of suppressor. So even though some of it does go backwards over the barrel, you still end up with a large, heavy suppressor that inch-for-inch is full of way more steel than usual. Seems like all those really narrow channels would be faster to get choked up by carbon deposits and such, too.

You can also reduce blowback and high gas pressures by having a really large blast chamber, and the BREVIS II does have a larger blast chamber than most cans. Like 2x the internal volume. Apparently they have a bit less blowback than usual. I don’t think it’s as significant a reduction as the OSS achieved, though. But the OSS is like 3.2 times heavier, adds a couple inches more barrel length, and their stat is 138 dB “at the shooter’s ear,” which is WAY louder than the BREVIS II’s 135-136 dB as measured per military standards, which is off to the side of the muzzle where it’s louder. The price on OSS vs. BREVIS II is pretty close, too. OSS is priced between the standard and Ultra 5.56 Brevis…

If the promise of the article is true, this is the future. The silencer supplanting the muzzle device in a major way.

I want ’em. But especially now that it’s suggested we pin them like muzzle devices, the question I always ask about a suppressor is more relevant than ever. How much sustained fire can these take? Many suppressors really strain after two or three magazines worth of rapid shooting. I want to run suppressors in tactical classes and in battle. I expect them to be the limiting factor and the first thing to fail under sustained fire. If they just shot off and self-destructed harmlessly that would be one thing, but baffle strikes and other serious failures can be dangerous. I’d really like some suppressors that I can trust for a few hundred intermediate rounds. Of course, there are different roles for suppressors and for most hunting guns I want the lightest suppressor possible and I only need it to stand up to as many shots as I’ll fire in practice at the range. A box of ammo at a time between cooling would be acceptable. Other cans fit somewhere in between the extremes of deer hunting and battle. What are these good for? And what’s the performance difference between the all-inconel and the titanium-inconel cans?

I love that 6.5mm and .338 cans are available. And the .338 is under 10oz! For what for most would be a do-everything rifle can! I now know what silencer I want for my ideal .338 Win Mag hunting rifle. With 3D printing I suppose it’s as easy to have a large variety of options as it is to design them, since each machine can probably make multiple designs equally well.

I’m wondering if this technology will also produce dramatic results with rimfire and pistol cans. Rimfire cans are already quite light and fairly short, but they could be better. The pistol potential excites me. Length has always been the problem with holstering and carrying suppressed pistols. We have seen some ways of dealing with it. Silencerco released offset suppressors, such as their Osprey series, which were still long. Short cans were released by various companies, but they were much less effective than standard-length suppressors. And now integrally suppressed pistols may enter the commercial marketplace via the Silencerco Maxim 9 (I’ve been waiting for them since I was a kid). I think this technology Delta P is introducing could allow for some great short suppressors, especially on integrally suppressed cans where a suppressor of any form could find much space within a pistol design that could be given over as suppressor volume for gas expansion. The engineers could dig out much of the pistol that is structurally unnecessary, with the only concern being ergonomics and heat management. These are exciting times. I believe that due to new techniques like this we’ll see a period of much new firearms development in the coming years as new possibilities emerge.

Inconel is used in nuclear reactors, rocket engines and afterburners (including blast nozzles/nacelles), turbocharger turbine blades, blast furnaces, space shuttle boosters… there are a few different alloy versions and I don’t know what these cans are made from, but operating temperatures of 1,800* F ain’t no thang since it maintains incredible strength at high temps. Way, way better than steel does. You’ll destroy the structural integrity of the barrel and shoot the rifling out the muzzle before the can loses strength. You could probably simultaneously use it as the forge and as the anvil to hammer out a new barrel 😉

On the Ti front, not entirely sure. The blast baffle and some of the lower structure on that can is Inconel and the rest of it is Ti. I don’t know as much about Ti in this regard (I’m familiar with Inconel from my racecar days). I know it’s lauded for its strength at high temperatures so I think it’s better than steel in this regard, but I don’t know how much so. May be more like an 1,100 *F max working temp thing. There are also a lot of Ti grades and alloys, too, and I have no idea what type the can is made from.

wow this is amazing. it is stunning how fast technology is advancing these days. I just watched a video the other day of two guys flying jetpacks beside a Commercial Airliner. Straight out of a movie, simply amazing.

Well I think a big factor is that they’re fairly low volume products (pun intended!). The market isn’t nearly as big as it would be if there wasn’t the $200 tax stamp and all the rest of the NFA legal concerns, etc etc, plus civilian sales were opened up in California and the 8-ish other states that still ban them (CA is the largest firearms market — by state — in the U.S. so if people there could buy suppressors it would be a big deal for the industry). There may be other expenses related to manufacturing them, but I actually don’t know if there are excise taxes or other things the manufacturer has to pay per suppressor they make. I think it’s easier for a firearm company like SIG to start making cans at a low cost, as they already own all of the super expensive machinery and are doing all of the serial number record keeping, etc, than a suppressor-only company that has to be profitable off of just lower-sales-volume suppressor sales. Which includes paying for the CNC equipment and software and all that jazz (or a DMLS unit(s) in this case).

I’d guess that these are not going to be popular on pistols, where the diameter will be a problem for the sights. But especially for AR-type platforms, where the sights are so far above the bore, the diameter does not seem important. Since I’m looking at an AR-10 type rifle next, that $1900 can is looking pretty good! I was looking at the Sig at 17.6 oz and 9.3″ long, for $795, but 4″ shorter and 8 oz lighter is causing me to twitch.

Now, I just have to figure out Silencer Shop’s new rules, so I can order something NFA again.

Yeah I don’t see them doing pistol cans as the booster assembly would ruin the whole “one monolithic piece of metal” thing. Although, I suppose it’s possible they could do a 9mm can that’s so lightweight it would run on a lot of pistols without a booster? Maybe. Maybe not. But they could also very easily offset the bore (a la SilencerCo Osprey) and keep the can under the pistol’s sights. But then again, that requires the can to be timed properly and that means either a lock washer or some sort of adjustable mount.

That price difference is huge, but then again half the length and half the weight is pretty huge, too haha. I understand your pain 😉

I can’t believe it hasn’t been brought up but I wonder how this would work if you had a baffle/”end cap” strike? My guess is you can’t just throw it back in the “printer” and fix it where as you can cut a weld on a competitors brand suppressors and have it repaired. Did Delta Point go into any detail if a repair for a baffle/end cap strike is possible? For that kind of money I hope it wouldn’t become a paper weight if something did ever happen to it.